This proposed study aims to identify nutritional and genetic factors that are associated with the development and/or extent of prostate cancer. About 150 newly diagnosed prostate cancer patients and 150 controls matched to the cases by age and ethnicity will be recruited. Among the subset of cases who choose to have prostatectomy, the aggressiveness of their cancer will be defined by pathological stage and grade. The objective is to examine if the following factors are associated with the risk of prostate cancer: (1) Fatty acid composition in buttock adipose tissue: It is hypothesized that specific categories and/or individual fatty acids are associated with the etiology of prostate cancer. (2) Anthropometric measurements (body mass index, waist-hip ratio, and body fat content): Patients with prostate cancer are hypothesized to have a high waist-hip ratio and percent body fat. (3) Germline polymorphisms of genetic markers that are known or hypothesized to be associated with development of the prostate: type II 5(-reductase, androgen receptor, vitamin D receptor, and three markers on long arm of chromosome 1 (1q24-25). (4) Serum vitamin D levels: It is hypothesized that patients with prostate cancer have low vitamin D levels.